1. Field of the Invention
The present invention relates to a controlling method of priority class setup of a communication packet and a system thereof, more specifically, to a controlling method of priority class setup in a multimedia communication system in which classified communication quality is provided according to a priority class attached to a communication packet.
2. Description of Related Art
Along with the growth of the Internet in recent years, technologies for accommodating various communicative applications of different requests for communication quality (such as telephone, video and data) into one packet network have been developed. For example, Differentiated Services [IETF Request for Comments 2475] (referred to as “Diffserv”) is a technology of attaching classification information to a communication packet and providing different communication quality in accordance with classes.
In a prior technology for providing classified communication quality as described above, correspondence is fixed between a communicative application and a class to be allocated. Accordingly, a user cannot alter such correspondence adaptively in accordance with a condition of communication.
Nevertheless, the communicative applications which request the same communication quality may require different classes depending on conditions (such as network congestion) or distances of communication. Accordingly, it is conceivable that optimum class allocation can be achieved by adaptively changing applied classes.
Moreover, implementation of such classified services may require an accounting system for charging different fees which vary according to types of services in each class. If the correspondence between a communicative application and a class is fixed therein, it incurs a problem of accounting practices unmatched with the requested communication quality.
It should be noted that there is also a technology of changing priorities inside a network. However, the technology does not allow a user to set up requests for communication quality at discretion.